MORE NEW CAR TECH FROM VOLKSWAGEN

SAN FRANCISCO— As fuel prices head frighteningly close to the $5 per gallon mark—even past it in some states—the question from many consumers has become a simple one: What's next? For Volkswagen, it's certainly clean diesel, as dealerships are ramping up to receive the 2009 VW Jetta TDI and its 50 miles per gallon. Two weeks ago today, VW took a step even further ahead by announcing the 2010 Golf Twin Drive Concept, a plug-in hybrid with a diesel range extender to boot. But what's beyond Twin Drive? Is Volkswagen ready for a hydrogen economy? We sat down with John Tilman, program manager for VW of America's advanced powertrain research program, and got the inside scoop on the real future of driving. —Basem Wasef

Many manufacturers have been working on hydrogen fuel cells. How's the VW program going?
Let's say that compared to some of the other OEMs, we're not as near term as some in terms of bringing something to market. We want to bring a vehicle to market when the infrastructure is there, which is a really big issue. Also, we absolutely need it to be dependable and durable, so consumers can drive and not feel that it's a (too) new technology, that's not comfortable for them. We want to make certain that when that car hits the market, consumer is ready and understands what it is, understands if there are any limitations with what they're getting. We want to make certain that we have the best solution that's well timed in the market.

How does hydrogen fit into our future fuels universe?
As you know, there's going to be a requirement in California and many states in the future for zero emissions vehicles. There's really only two solutions for zero emissions: battery/electric, of course, and fuel cell. The only limitation with battery/electrics is range. Fuel cells don't really have those limitations, per se. We can actually get 200-300 mile ranges, depending on our storage capacity. And consumers are very comfortable with that scenario. They fill their cars now, go 300 miles, fill them again. With battery/electrics, you have these long charge cycles: 2, 3, 5, 10 hours. Consumers aren't really going to accept that as long-term solutions for long distance vehicles.

Does that mean that you could combine the two—EVs and fuel cells?
That is one solution. The best solution for a fuel cell, actually, is a plug in hybrid with a fuel cell range extender. The reason for that, you can have a fuel cell at 20-30 kilowatts, steady state, most efficient operation for a fuel cell, plug it in for the first 80-100 mile range, and then the fuel cell will extend the range to 200-300 miles.

Do you have any particular angle that you would take? That sounds similar to the GM E-Flex system. Is there a Volkswagen twist?
Actually, yes. We're working on high temperature technology. A fuel cell that runs at a higher temperature has much higher efficiency. But because of the fact that it doesn't have the limitations of a low temperature system, we can actually downsize, lower the parts count, get a more dependable system for the consumer. We're the only manufacturer right now doing a high temperature system in a light duty application.

So how does the high temperature system work, exactly?
We run it between 120 and 160 degrees Celsius average, compared to systems that are 80 to 100 degrees Celsius, their efficiencies are lower, and they actually run water as a coolant. We actually run a more viscous fluid, more like an oil, as a coolant. And that downsizes the coolant system.

These are temperatures inside?
The actual ambient temperature of the stack is 120-160 degrees. It's not the outside of the stack itself.

What are the cycle demands of that high temperature? Does it take longer to get to operating mode?
If we actually run the mode of operation correctly, you'd be able to get in, start the car, and run it without really noticing any difference. What we would do in that case is likely step it. Basically, we'd have a low power setting under 30 or 40 precent of low power, then when it warms up, go to a higher power and then full power setting. That's the most efficient operation for a high temperature system.

What are some of the tradeoffs with hydrogen in general?
Right now, the easiest way and most industrially accessible way (to make hydrogen) is steam reformation of natural gas. That means you get energy from steam, the byproduct of natural gas's reaction to it, and so there are issues with the current means of getting hydrogen. Long term, though, of course you can get hydrogen from electrolysis of water, probably the way that would make the most sense. Then you could actually electrolyze the water onsite, in the home possibly, with solar panels or wind. That's a totally green solution. If you want to go mid-term between that solution and where we're at now, you would go with a micro steam reformer in your garage. It's a shoebox size device sitting on your wall, uses natural gas which is already piped into the home, and you could directly put [hydrogen] into the car. So let's say in a 5-7 hour timeframe you could go from zero or low fuel to full fuel overnight.

How far out do you think we are from that kind of technology?
Actually, Honda already has a solution for that, and VW is part of a consortium of manufacturers developing a device that will go in the garage. It costs about $50,000. We're working on a solution with eight other OEMs, I can't mention the names because of NDAs at the moment, but we're developing another home solution not based on the Honda technology, that we'll be able to license and sell in our own showrooms when these vehicles hit the showrooms.

Are you broadening your scope at all, or are you focusing on hydrogen?
The reality is, when hydrogen fuel cell vehicles come to the market, they won't be alone. There will be diesel and biofuels of different types. There will be gas to liquid type fuel where you convert cellulose to liquid fuel, you can make diesel, gasoline, many different fuels out of that. There will be electric cars too. We don't want to put ourselves in a position where we have only solution of the market. We have to be looking at multiple solutions. So we're looking at multiple technologies including pure EVs and plug in hybrids with fuel cell range extenders, different kinds of range extenders, even. So the range extender can be based on biofuel, fuel cell or gasoline, different solutions for different market segments. There will be electric vehicles in San Francisco; short driving distances, easy to deal with. But if you're in Kansas, that won't be the solution.

Do you see different technologies spreading across the product line to suit different driving styles?
One of the advantages of electric—whether it's battery electric or fuel cells—is that you literally change the software. A consumer could do it, I suppose, but if they want more power off the line we can suit their needs. They'll sacrifice the power towards the top end of the powerband. We can customize that particular situation to the consumer. Current technologies don't really allow that, but as we move forward and it becomes more software based, we can.

Certain car manufacturers are allied with different companies, such as Nissan's relationship with NEC. Does VW have special relationships with certain companies?
We do have working relationships with different research companies. We recently announced a battery project with Sanyo, I believe, a long-term five year project to develop the next generation of batteries. We are not just tied to them, we want to keep our options open. We've got about 4 or 5 really good, high quality battery chemistries. We don't want to limit ourselves to just one company, and that technology, and that chemistry. We have to keep our options open when the market solution arrives.

How much of your team is in Sacramento?
The entire advanced powertrain team is there now. But it's a very small team. In the U.S. right now it's two. In the entire U.S. We're really, really busy. But we are constantly finding that Germany's starting to see the value in having German staffers on the ground in North America to really answer the questions that are coming up. And the questions are coming up faster than the answers are. So we need more staff, and in fact I'm going to Germany next week to discuss the issue of doubling our staff in the next year to cover the number of issues that are coming up.

I recently read about regenerating energy from exhaust heat. What are your thoughts on that?
That is possible. There are piezoelectric devices that take the difference between ambient temperature and generating electricity off of that, but they're finding that the amount of energy generated is fairly low. It's good quality. It will power devices, but it won't power systems. There is no solution for getting as much energy out as you put in. You only really supply it a small portion of our energy. But we are looking at it.